That’s quite a lot of money.
Do you know of any cheap standalone L1+L2 receivers? In open sky conditions they are pretty good, as tested by some Xiaomi phone users on our FB group.
But I don’t want to buy a phone just to record tracks.
I saw some cheap “multiband” modules on aliexpress, but I don’t believe they are really multiband. I think it is better to take some old used u-blox NEO-M8* / NEO-M9* modules than to buy fake “multiband” module with unknown precision. As I understand, it is better to use L1 receiver with correction than multiband receiver without correction data.
People I know on OSM using RTK include Jean-Guilhem Caiton (jgc) with ublox modules in France & in the UK both Russss and Firefishy have recently acquired them. There’s also a thread in this forum in Russian on RTK. It’s possible that sharing experience & advice would be useful. I felt that perhaps this was something a national association could invest in: however, in the UK we now have accurate open data on cadastral parcels which fulfills the purpose of high-quality image alignment.
The Polish state NTRIP caster costs money for live RTK, but for the subsequent correction of the tracks at the PC at home you can download the correction data (RINEX files?) of the stations for free!
In addition, there are many private people (farmers?) who operate similar fixed stations for live RTK for free (http://rtk2go.com/ or 184.108.40.206:2101, for Poland 220.127.116.11:2103 could also work, then you don’t see the extremely long list of all data streams in the world but only the Polish ones).